Scaffold jack



p 28, 194?6 E. L. JONES 2,281,039

SCAFFOLD JACK Filed Sept. 23, 1940 2 Sheets-Sheet l jg, .Z

Inventor 4 M67? L. Jon/5 A iiorney April 28, 1942.

- E. L. JONES SCAFFOLD JACK File'd Sept. 23, 1940 2 Sheets-Sheet 2 IInventor 54410? L. JONES A tiorney Patented Apr. 28, 1942 UNHTED STATESSCAFFOLD JACK Elmer L. Jones, Indie, Calif.

Application September 23, 1940, Serial No. 357,963

1 Claim.

This invention relates to scaffold jacks and an object of the inventionis, generally, to improve upon such jacks as are now known and used forthe purpose stated.

A further object of the invention is to provide a scaffold jack whichmay also be used with equal facility by carpenters and analogousbuilding tradesmen as a sawhorse.

The invention together with its objects and advantages will be bestunderstood from a study of the following description taken in connectionwith the accompanying drawings wherein- Figure 1 is an elevational viewillustrating the application of the invention and as used in theconstruction of a scaffold.

Figure 2 is a top plan view of the scaffold jack.

Figure 3 is an elevational view of the scaffold jack, and

Figure 4 is a view through the jack with certain parts shown in sectionand other parts shown in elevation, and illustrating certain detailshereinafter more fully referred to.

Referring more in detail to the drawings it will be seen that in thepreferred embodiment thereof the device which may be termed acombination scaffold jack and sawhorse in the preferred embodimentthereof comprises 'a cross-bar 5 supported adjacent the opposite endsthereof by leg structures 6.

Each of the leg structures 6 embodies a pair of standards I1 which aredisposed so as to converge as they approach the upper ends thereof,

and at said upper ends the standards 1 are con Also intermediate theends thereof the standards I are connected together and braced relativeto one another through the medium of a brace member ID that at itsrespective opposite ends is provided with flanges ll bolted or otherwisesecured as at [2 to the standards I as shown.

Also rising vertically from the brace member is a post 13 that at oneend is suitably anchored as at M to the cross-member ID. The post l3extends upwardly through suitable aligned openings provided therefor inthe cross-bar and bight of the bracket 8 as will also be clearly seenfrom a study of Figure 4.

The posts l3 support in suspended position therebetween, and at thedesired position of vertical adjustment a scaffold board-supportingcrossmember l4 which may be in the form of an oblong bar of wood, metal,or other suitable material.

The member M has fastened to each end thereof through the medium of aU-bolt 5 a suspension element l6. The element 56 is in the form of aplate formed at one end with a hinge eye ll that is engaged with theU-bolt as shown, and at the free end thereof with an opening throughwhich the post 13 extends.

It will thus be seen that the weight of the member l4 and the scaffoldplank supported thereby will exert a downward pull on the suspensionelements It so that the same will frictionally engage the posts [3 forholding the member M in the desired suspended positioned between theposts I 3.

In using the jack for scaffold-building purposes, a pair of such jacks,as shown in Figure 1, may be used. When so used the upper platform plankH; of the scaffold is extended between and supported by the members 14,and a lower scaffold platform plank or board may be, if desired,supported between the members 5 of the jacks through the medium ofclamping plates 20.

In connection with the clamping plates 20 it will be seen that each jackis provided with a clamping plate 20 between which and a member 5 of thejack one end of the scaffold plank I9 is clamped; the clamping plate 20being supported beneath the bottom of the member 5 through the medium ofdepending bolts 21 equipped with nuts 22. (See Figure 3.)

It will also be appreciated that when desired the jacks, with or withoutremoving the members l4, may be used as sawhorses.

It will also be apparent that with the use of these jacks scaffolds maybe readily and easily erected, and as easily taken down; and thesimplicity of the invention, together with the many advantages thereofare believed to be clear to those skilled in the art without requiringmore detailed description of the invention.

Having thus described the invention what is claimed as new is:

A scaffold jack comprising an elongated cross piece, a leg structureadjacent each end thereof and each structure including a pair ofdownwardly diverging members, means for connecting said members at theirupper ends to the cross piece and a brace plate extending between themembers of each pair intermediate the ends thereof. and

connected therewith, a pair of posts extending upwardly from the crosspiece and each post passing through the cross piece to a brace plate towhich the post is welded, a second cross piece extending between theposts and of less length than the distance between the two posts, plateshaving openings therein through which the posts pass and means forhinging the inner ends of the plates to the upper face of the secondcross piece adjacent the ends of the cross piece.

ELMER L. JONES.

